Why are Quick Panels Used?

Quick Connect Panels are used to (1) provide a temporary source of power when necessary, and (2) to connect load banks for backup power test events.

Temporary Power

A Quick Connect Panel is used as an input device to connect a temporary generator to a building's electrical distribution system through either an integrated or stand-alone Manual Transfer Switch. By doing so, a facility without a permanent generator can obtain emergency power when outages occur. Commonly, a rented generator is transported to a site when needed, then disconnected and removed from that site when utility power returns. This solution offers small and mid-size facilities a backup power solution without the initial capital outlay of a permanent genset and the ongoing expense associated with the testing, maintenance, and repair of a permanent unit. This can be an adequate solution for a facility that can tolerate power outages until a generator can be delivered and connected. For more information about this type of application, review ASCO’s white paper entitled California Power Outages.

Facilities with one or more permanent standby generators commonly use Quick Connect Panels for backup power. There are two reasons that facilities do so. The first is that a temporary generator can provide power to the load when one of a facility’s permanent generators is taken offline for service or becomes dysfunctional. In these applications, the quick connects enable a temporary generator to become a “backup-for-the-backup”.

The second reason is a logical extension of the first. For regulated mission-critical facilities (such as a hospital) with only one permanent generator, a connecting means is required by Article 700.3 of the National Electrical Code^®. Figure 2 shows such an arrangement. For more information about this application, review the ASCO Technical Brief entitled NEC Requirement for Permanent Manual Switching Means.

Figure 2: A power system of a regulated mission-critical facility equipped with one permanent generator and a Quick Connect Panel.

Load Testing

A best practice is to regularly test backup power sources under load. Regular performance testing verifies that a backup power system is ready to supply adequate power when an outage occurs on the primary source. Again, regulated mission-critical facilities may be required to do so by codes such as the National Electrical Code^® and NFPA 110 – Standard for Emergency and Standby Power Systems. For more information regarding NFPA 110, review Part 1 and Part 2 of the ASCO white paper entitled NFPA 110 Overview.

When testing backup power systems, some facilities are reluctant to use live building load. In addition, the amount of live load at the time of testing may be a small fraction of the total capacity of the backup power system. Notably, most backup power generators are powered by diesel engines, which typically must operate at a minimum load of 30 percent or more to avoid a condition known as wet stacking. For these reasons, a permanent or temporary load bank is often provided to ensure adequate load for a meaningful test. Providing a quick-connect output panel enables a facility to use a temporary load bank to provide adequate load. This arrangement avoids the larger initial cost of purchasing and installing an equivalent permanent load bank.

Accessing Both Supplemental Power and Supplemental Load

Dual-Purpose Quick Connect Panels feature both input and output panels in one device. These can be used singularly or together to connect power sources and load banks for all of the reasons described above.

How Else Do ASCO QCPs Vary?

Quick Connect Panels also vary by whether they integrate a transfer switch and whether they integrate one or more circuit breakers for the power sources or loads.

Integrated Transfer Switch

If a temporary power source is added to a backup power system, a transfer switch is needed to select between the supplemental genset and the permanent genset. Some applications will benefit from using separate devices, such as an indoor manual transfer switch to transfer load between the permanent and temporary power sources through an outdoor Quick Connect Panel. This arrangement can allow direct control of the transfer switch from an indoor power equipment room and a convenient location alongside a paved area for connecting a temporary generator. Other applications may be well served by using a single, integrated, outdoor unit that combines a manual transfer switch and a quick connect panel in a single enclosure (Figure 2). This solution can reduce the net equipment footprint, installation labor, and the overall cost of the solution.

Figure 3: A Manual Transfer Switch with dual-purpose Quick Connects provides supplementary backup power and load testing connectivity through a single device.

Integrated Circuit Breakers

Both power sources and loads may require breakers to open circuits when overcurrents occur. ASCO Quick Connect panels make it possible to integrate circuit breakers for outputs to a load bank as well as for inputs from a utility feed, a permanent generator, a temporary generator, or both permanent and temporary power sources. Integrating breakers in this way can simplify the specification, procurement, and installation of the complete solution.

Quick Connect Panels by Application

The following table summarizes the entire range of ASCO Quick Connect Products.